Field of the Invention
The present invention relates to endoscopes, and particularly, to an endoscope in which a treatment tool inserting tube and a connecting pipe, in which a treatment tool is inserted, are fixed through a fixing sleeve.
Description of the Related Art
Conventionally a medical diagnosis using an endoscope is widely made in medical fields. Particularly an imaging element of a charge-coupled device (CCD) or the like is built into a distal end rigid portion of an insertion portion in the endoscope inserted into a body to take an image in the body. The image is subjected to signal processing in a processor device to be displayed on a monitor. A doctor observes the image to make a diagnosis or insert a treatment tool from a treatment tool inserting port and perform treatment such as collection of samples or removal of polyps.
The endoscope is provided with an operating unit that is grasped by a practitioner to be operated and an insertion portion a proximal end of which is connected to the operating unit to be inserted into the body, wherein a proximal end of a universal cable is connected to the operating unit. A connector in a distal end of the universal cable is removably connected to an optical source device or a processor device, thereby making the endoscope become in a usable state.
In such an endoscope, there has been recently used the treatment tool that is large in size and is high in bending stiffness. The treatment tool is inserted into the insertion portion from the treatment tool inserting port provided in the operating unit of the endoscope and is led out to an exterior from a treatment tool leading-out port provided in the distal end rigid portion of the endoscope.
A proximal end of a treatment tool inserting tube (called a forceps tube as well) having flexibility is connected to the treatment tool inserting port, the treatment tool inserting tube is disposed from a flexible portion to a curved portion of the insertion portion, and a distal end of the treatment tool inserting tube is fitted outward on a proximal end of a metallic connecting pipe (called a forceps pipe as well) (for example, refer to Japanese Patent Application Publication No. 02-021852 or Japanese Patent Application Publication No. 2002-209829). Thereby the treatment tool inserting tube and the connecting pipe are connected to cause the distal end of the connecting pipe to be communicated with the treatment tool leading-out port of the distal end rigid portion.
In a state where a puncture needle as the treatment tool is inserted into a flexible sheath, the puncture needle is inserted with the sheath from the treatment tool inserting port and is led out from the treatment tool leading-out port through the treatment tool inserting tube and the connecting pipe. The bending stiffness of the sheath is lower than the bending stiffness of the puncture needle, but is controlled by the bending stiffness of the puncture needle following the insertion of the puncture needle. In a case of the puncture needle, the puncture needle with the sheath is called the treatment tool.